Theodolite horn magnifier

Horn magnifier for the "A" frame telescopic theodolite.

ID:	NAV1462.6
Type:	Theodolite horn magnifier
Display location:	Not on display
Creator:	Worthington & Allan
Date made:	circa 1830
Credit:	National Maritime Museum, Greenwich, London. Caird Fund.
Measurements:	Overall: 6 mm x 35 mm x 27 mm
Parts:	Theodolite Theodolite (NAV1462.1) Theodolite telescope (NAV1462.2) Theodolite telescope lense cap (NAV1462.3) Theodolite eyepiece (NAV1462.4) Theodolite eyepiece (NAV1462.5) Theodolite horn magnifier (NAV1462.6) Theodolite box. (NAV1462.7)